Field of the Invention
The invention relates to a transistor and a fabricating method thereof, and more particularly, to a thin film transistor and a fabricating method thereof.
Description of Related Art
Accompanied by the significant progress in information technologies, display devices with various specifications have been applied in screens of all sorts of consumer electronic products including mobile phones, notebook computers, digital cameras and personal digital assistants. Among these displays, liquid crystal display (LCD) and organic light emitting diode (OLED) have become mainstream products in the market owing to the advantages including light weight and low power consumption. Manufacture process of LCD and OLED includes disposing an array of semiconductor devices including a thin film transistor (TFT).
With resolution of a display getting higher, a size of the thin film transistor is getting smaller accordingly. A thin film transistor with a self-align top-gate structure has been developed to solve problems such as limitations to alignment during a lithography process, and parasitic capacitance of gate-to-drain and gate-to-source (i.e., Cgd and Cgs). However, in conventional art, indium gallium zinc with low resistance is provided by sputtering entire surface of an aluminum thin film with a thickness controlled at approximately 5 nanometers, followed by performing an oxidation reaction to an indium gallium zinc oxide (IGZO) with high resistance and the aluminum thin film in an annealing process. Accordingly, in conventional art, problems such as the thickness uniformity of the aluminum thin film and the completion of oxidation reaction can result in the malfunction of device.